I am aware that the factory cam on my 1996 F-150 is installed with 4 degrees of retard. I am also aware that if I correct that by installing it "straight up" (in theory) I will improve low RPM torque and fuel economy. The question I have is will this upset the computer? I installed a Cloyes metal cam gear at least 10 years ago, and at the time I did not change the crank gear because I saw no need. I also was unaware of the factory retard built in to the crank gear on the later engines. I still have the crank gear that came in the kit, and it is marked for retard, straight up and advance. Since the pan gasket is starting to leak, and I am going to have to fix it soon anyway, I may as well install the crank gear and bump the timing to 0 degrees. Has anyone with EFI done this? Especially anyone with EFI and OBDII? I won't mess with it unless I am sure it won't give me drivability issues with the EFI. It would be nice to have a bit more grunt for pulling overdrive now that I have it. The engine likes cruising at 1,500 RPM at 60 MPH, but even slight throttle pressure increases cause the AOD to kick down (like climbing a slight grade). If the engine were more efficient at 1,500 then this might not be an issue. Unfortunately my AOD is calibrated for a 5.0L V8 so it probably is not too keen on being at 1,500 cruise anyway, especially since I am running 31 inch tires and the donor truck used 235 75 R15s. I have contemplated this for a long time, the new to me AOD is just furthering the case for it. I want to do it even if I swap the AOD for a C6.

So, have any EFI people done this and had issues? If not, did you see an increase in responsiveness? Fuel Economy? Thanks for the input.

 

I don't have an efi rig but according to Crower's tech dept all of their cams have 4 degrees advanced from straight up and still say they are computer friendly like this One. So being 8 degrees advanced from stock and still being computer friendly I don't see why a stock cam straight up wouldn't work. I'm no expert but maybe someone else will chime in. Good Luck!

 

Thanks! That is a good point. I wonder if anyone has run anything like this with an OBD2 1996? If it works, then I'll gladly try it on my truck. I don't mind having to run higher octane due to increased cylinder pressure if the the fuel economy boost will outweigh the increased cost of the fuel.

 

Advancing or retarding the cam shouldn't affect the EEC. Computer compatible *usually* relates to lobe separation, duration - and speed density type EFI. Lumpy idling cams won't work well at all with an SD EFI system but are *usually* no worries with MAF.

 

OK, another question: On the "retarded" 300s, is the cam retard built in to the cam, or is the cam retard built into the factory crank gear and/or cam gear?

 

It's ground into the cam itself.